U2023: Vehicle network communication fault reported between control modules
What Does U2023 Mean?
U2023 is a diagnostic trouble code associated with vehicle network communication fault reported between control modules. FixIt has matched this code to 8 NHTSA owner reports across 1 vehicle model; the strongest signal is Ford Escape.
This page prioritizes real-world complaint patterns over generic lookup-table text. Use U2023 as the starting point, then confirm the exact manufacturer definition with a scan tool that can read the affected module. Do not replace expensive modules from the code alone; validate power, ground, wiring, sensor data, and companion codes first.
Symptoms of U2023
- ⚠️ Multiple warning lamps at the same time
- ⚠️ Intermittent no-start, limp-mode, or module offline symptoms
- ⚠️ Scan tool cannot communicate with one or more modules
- ⚠️ Symptoms may appear after low battery voltage or prior electrical work
Common Causes
- 🔍 Low battery voltage or weak charging system causing module resets
- 🔍 CAN/network wiring fault, corrosion, or loose connector
- 🔍 Module power/ground loss
- 🔍 Failed control module after wiring and voltage checks pass
U2023 Reports by Year
Real Owner Reports
From NHTSA complaint database — actual owner descriptions.
"IN AUG 2012 WE WERE ON OUR WAY BACK FROM A VACATION AND OUR ABS LIGHT CAME ON, ALONG WITH A FLASHING 4X4 LIGHT. WE HAD NO IDEA WHAT IT WAS OR WHAT TO DO. THE VEHICLE DROVE FINE AND STOPPED FINE, EXCEPT FOR A COUPLE OF TIMES IT FELT AS IF THE ABS ENGAGED ON DRY CEMENT. WE STOPPED TO EAT AND SHOP FOR A FEW HOURS AND THE LIGHTS WERE OFF WHEN WE GOT BACK IN THE VEHICLE. THEY DIDN'T COME ON AGAIN UNTIL A FEW DAYS AGO (JAN"
— Ford Escape owner, 08/01/2012
"ON FRIDAY JULY 18TH 2014 @ 5:42 PM I WAS DRIVING MY SUV AND I GOT 3 ERRORS 1. THE ABS LIGHT CAME ON 2. THE BRAKE LIGHT CAME ON AND 3. THE INFORMATION PANEL SAID SERVICE BRAKE SYSTEM. WHEN I GOT OFF THE FREEWAY I NOTICED MY BREAKS WERE NOT RESPONDING I IMMEDIATELY PUT THE CAR ON NEUTRAL PUT MY HAZARD LIGHTS ON AND PULLED THE HAND BREAK WHICH HAD NO EFFECT. I PUMPED THE BREAKS AND NO RESPONSE FROM THE CAR, I TOOK OFF T"
— Ford Escape owner, 07/18/2014
"TL* THE CONTACT OWNS A 2008 FORD ESCAPE. THE CONTACT STATED THAT WHEN THE DRIVER STARTED THE ENGINE, THE BRAKE WARNING LIGHT ILLUMINATED. THE CONTACT ALSO ADVISED THAT THE BRAKE PEDAL FELT LOOSE WHEN IT WAS ENGAGED. THE VEHICLE WAS TAKEN TO AN UNKNOWN MECHANIC THAT PERFORMED A DIAGNOSTIC AND ADVISED THAT THE VEHICLE BRAKE HYDRAULIC CONTROL UNIT FAILED. THE CONTACT ALSO MENTIONED THAT THE BRAKE HYDRAULIC CONTROL UNIT "
— Ford Escape owner, 01/06/2020
Source: NHTSA Complaints Database
Most Reported Vehicles for U2023
Based on NHTSA owner complaint data.
| # | Vehicle | Reports |
|---|---|---|
| 1 | FORD ESCAPE | 8 |
U2023 Reports by Vehicle
Detailed NHTSA complaint analysis for each vehicle model.
Diagnostic Tips
- Test battery state of charge and alternator output first
- Scan every module and document which modules are offline or reporting U2023
- Inspect CAN wiring and connectors near recent repair areas or water intrusion points
- Repair network wiring/power/ground faults before replacing a control module
Common Mistakes to Avoid
- ❌ Replacing a control module before checking battery voltage, grounds, and connectors.
- ❌ Using a generic scanner that cannot read ABS, body, steering, or network modules for this code family.
- ❌ Clearing the code without recording freeze-frame data and companion codes first.
Frequently Asked Questions
What does U2023 mean?
Can I drive with U2023?
What should I check first for U2023?
What To Do Next
Possible Fixes
- 🔧 Test battery state of charge and alternator output first
- 🔧 Scan every module and document which modules are offline or reporting U2023
- 🔧 Inspect CAN wiring and connectors near recent repair areas or water intrusion points
- 🔧 Repair network wiring/power/ground faults before replacing a control module
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Find your vehicle above
Click your make and model for real owner reports and common causes specific to your vehicle.
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Check for recalls
Go to nhtsa.gov/recalls and enter your VIN. Free repairs if covered.
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Get a professional diagnosis
A code alone doesn't identify the exact failed part. A diagnostic ($50–$150) pinpoints the root cause.